A company manufactures 2 models of MP3 players. Let x represent the number (in millions) of the first model made, and let y represent the number (in millions) of the second model made. The company's revenue can be modeled by the equation R(x, y) = 90x+80y - 2x² - 3y² - xy Find the marginal revenue equations R₂(x, y) - R₂(x, y) - We can achieve maximum revenue when both partial derivatives are equal to zero. Set R0 and R₁ 0 and solve as a system of equations to the find the production levels that will maximize revenue. Revenue will be maximized when: